1. Field of the Invention
The invention relates to a felt belt, especially a press felt for a paper—, cardboard- or tissue machine.
2. Description of the Related Art
Felt belts, especially press felts for paper—, cardboard- or tissue machines normally include a basic structure which provides the dimensional stability of the felt, and which is furnished with one or more fibrous nonwoven layers.
In the past the objective in the development of new press felts was oftentimes to replace the felt belts through a modular composition of individual components and to thereby replace the woven structures.
WO89/03300 for example shows felt belts composed of modules. Here, modules are suggested which consist of a laid structure of longitudinal threads which is bonded with one fibrous nonwoven layer, and also of modules which consist of a laid structure of cross threads which is bonded with one fibrous nonwoven layer.
In order to simplify the production of modular press felts of this type it is further suggested in EP 1837440A1 to produce the tensile load absorbing longitudinal reinforcement module from a laid structure of longitudinal threads which is bonded with a fibrous nonwoven layer in one winding process, and to construct the cross-reinforcement module which is used to increase the transverse stability from several cross-reinforcement module segments which extend only along part of the length of the press felt and which are produced in a first manufacturing step, also through a winding process like the longitudinal reinforcement module and which, in a subsequent manufacturing step are trimmed to the width of the press felt that is to be produced, and are oriented with their threads transversely to the laid structure of longitudinal threads, and arranged in tandem in longitudinal direction of the felt.
The known modular press felt concepts consist of laid structures of longitudinal threads and of laid structures of cross threads, whereby the two laid structures are bonded with each other through only one fibrous nonwoven layer. A disadvantage of these structures is that such laid structures often only provide a very limited internal volume in the press felt. Also, since the laid structures of longitudinal and cross threads can move against each other they move aside for each other when running through the press nip, which can lead to a further reduction of the internal hollow space volume and consequently to a reduction in the water absorption capacity.
What is needed in the art are press felts in which the aforementioned disadvantages no longer occur and which, in addition are cheaper to produce than the press felts which are known from the current state of the art.